Auditory-Perceptual Assessments of Cough: Characterizing Rater Reliability and the Effects of a Standardized Training Protocol.

INTRODUCTION: Auditory-perceptual assessments of cough are commonly used by speech-language pathologists working with people with swallowing disorders with emerging evidence beginning to demonstrate their validity; however, their reliability among novice clinicians is unknown. Therefore, the primary aim of this study was to characterize the reliability of auditory-perceptual assessments of cough among a group of novice clinicians. As a secondary aim, we assessed the effects of a standardized training protocol on the reliability of auditory-perceptual assessments of cough. METHODS: Twelve novice clinicians blindly rated ten auditory-perceptual cough descriptors for 120 cough audio clips. Standardized training was then completed by the group of clinicians. The same cough audio clips were then re-randomized and blindly rated. Reliability was analyzed pre- and post-training within each clinician (intra-rater), between each unique pair of raters (dyad-level inter-rater), and for the entire group of raters (group-level inter-rater) using intraclass correlation coefficients and Cohen's Kappa. RESULTS: Pre-training reliability was greatest for measures of strength, effectiveness, and normality and lowest when judging the type of expiratory maneuver (cough, throat clear, huff, other). The measures that improved the most with training were ratings of perceived crispness, amount of voicing, and type of expiratory maneuver. Intra-rater reliability coefficients ranged from 0.580 to 0.903 pre-training and 0.756-0.904 post-training. Dyad-level inter-rater reliability coefficients ranged from 0.295 to 0.745 pre-training and 0.450-0.804 post-training. Group-level inter-rater reliability coefficients ranged from 0.454 to 0.919 pre-training and 0.558-0.948 post-training. CONCLUSION: Reliability of auditory-perceptual assessments varied across perceptual cough descriptors, but all appeared within the range of what has been historically reported for auditory-perceptual assessments of voice and visual-perceptual assessments of swallowing and cough airflow. Reliability improved for most cough descriptors following 30-60 min of standardized training. Future research is needed to examine the validity of auditory-perceptual assessments of cough by assessing the relationship between perceptual cough descriptors and instrumental measures of cough effectiveness to better understand the role of perceptual assessments in clinical practice.

Rehabilitating Cough Dysfunction in Parkinson's Disease: A Randomized Controlled Trial.

BACKGROUND: Disorders of airway protection (cough and swallowing) are pervasive in Parkinson's disease (PD) resulting in a high incidence of aspiration pneumonia and death. However, there are no randomized controlled trials comparing strength and skill-based approaches to improve airway protection in PD. OBJECTIVES: The aim of this study was to compare expiratory muscle strength training (EMST) and sensorimotor training for airway protection (smTAP) to improve cough-related outcomes in people with PD. METHODS: Participants with PD and dysphagia were recruited for this prospective phase II randomized-blinded controlled clinical trial. Participants completed baseline assessment, 5 weeks of EMST or smTAP, and a post-training assessment. Primary outcome measures included maximum expiratory pressure (MEP) and voluntary cough peak expiratory flow rate (PEFR). Mixed effects models were used to assess the effects of EMST and smTAP on outcomes. RESULTS: A total of 65 participants received either EMST (n = 34) or smTAP (n = 31). MEP improved from pre- to post-treatment for smTAP (P < 0.001, d = 0.19) and EMST (P < 0.001, d = 0.53). Voluntary PEFR increased from pre- to post-treatment for smTAP (P < 0.001, d = 0.19) and EMST (P < 0.001, d = 0.06). Moreover, reflex cough PEFR (P < 0.001, d = 0.64), reflex cough expired volume (P < 0.001, d = 0.74), and urge to cough (P = 0.018, OR = 2.70) improved for the smTAP group but not for the EMST group. CONCLUSIONS: This clinical trial confirmed the efficacy of smTAP to improve reflex and voluntary cough function, above and beyond EMST, the current gold standard. © 2022 International Parkinson and Movement Disorder Society.

Sensorimotor Cough Dysfunction in Cerebellar Ataxias.

Cerebellar ataxias are neurological conditions with a high prevalence of aspiration pneumonia and dysphagia. Recent research shows that sensorimotor cough dysfunction is associated with airway invasion and dysphagia in other neurological conditions and may increase the risk of pneumonia. Therefore, this study aimed to characterize sensorimotor cough function and its relationship with ataxia severity. Thirty-seven participants with cerebellar ataxia completed voluntary and/or reflex cough testing. Ataxia severity was assessed using the Scale for the Assessment and Rating of Ataxia (SARA). Linear multilevel models revealed voluntary cough peak expiratory flow rate (PEFR) estimates of 2.61 L/s and cough expired volume (CEV) estimates of 0.52 L. Reflex PEFR (1.82 L/s) and CEV (0.34 L) estimates were lower than voluntary PEFR and CEV estimates. Variability was higher for reflex PEFR (15.74% coefficient of variation [CoV]) than voluntary PEFR (12.13% CoV). 46% of participants generated at least two, two-cough responses following presentations of reflex cough stimuli. There was a small inverse relationship between ataxia severity and voluntary PEFR (ß = -0.05, 95% CI: -0.09 - -0.01 L) and ataxia severity and voluntary CEV (ß = -0.01, 95% CI: -0.02 - -0.004 L/s). Relationships between reflex cough motor outcomes (PEFR ß = 0.03, 95% CI: -0.007-0.07 L/s; CEV ß = 0.007, 95% CI: -0.004-0.02 L) and ataxia severity were not statistically robust. Results indicate that voluntary and reflex cough sensorimotor dysfunction is present in cerebellar ataxias and that increased severity of ataxia symptoms may impact voluntary cough function.

The Role of Aspiration Amount on Airway Protective Responses in People with Neurogenic Dysphagia.

The aim of this study was to examine relationships between the presence vs. absence of an aspiration-related airway protective response (i.e., coughing or throat clearing) with aspiration amount, trial volume, disease diagnosis, and disease duration in people with neurologic disease. A secondary analysis was completed of flexible endoscopic evaluations of swallowing (FEES) in people with neurologic disease. Thin liquid boluses with endoscopically confirmed aspiration were included. Aspiration amount was measured for each trial using the visual analysis of swallowing efficiency and safety (VASES). Statistical analyses were used to (1) compare aspiration amount between swallows with vs. without an airway protective response and (2) examine if trial volume, disease duration, and disease diagnosis were related to the presence of airway protective responses when controlling for aspiration amount. 422 aspirated swallows across 86 FEES were analyzed. Of the 59 people who aspirated more than once, 66.1% exhibited variability in the presence vs. absence of an airway protective response. Statistical analyses revealed airway protective responses were significantly related to aspiration amount (p < 0.001; Marginal R2 = 0.46) and disease duration (p = 0.036, L.R. = 4.35) but not trial volume (p = 0.428) or disease diagnosis (p = 0.103). The participants in this study were less likely to cough or throat clear when having smaller amounts of aspiration or longer disease durations. Future research is needed to examine if aspiration amount is related to airway protective responses in healthy adults and across other patient populations.

Quantifying Impairments in Swallowing Safety and Efficiency in Progressive Supranuclear Palsy and Parkinson's Disease.

Dysphagia is a largely inevitable symptom in both progressive supranuclear palsy (PSP) and Parkinson's disease (PD). To date, comparative studies in these diseases have failed to detect differences in the severity of impairments in swallowing safety or efficiency, potentially due to small sample sizes and outcome measures with low sensitivity. Therefore, this study sought to address these limitations by using novel measurement methodology to comprehensively compare swallowing safety and efficiency impairments between these populations in order to better understand whether differences may exist and guide clinical management. Twenty-four participants with PSP and 24 with PD were matched for disease duration and completed flexible endoscopic evaluations of swallowing. A visual analog scale and penetration-aspiration scale quantified swallowing safety and efficiency. Bayesian multilevel models compared the frequency, severity, and variability of swallowing impairments. Individuals with PSP demonstrated greater impairments in swallowing safety, including deeper and more variable airway invasion and more frequent vocal fold and subglottic residue. Swallowing efficiency was also more impaired among individuals with PSP, including more frequent hypopharyngeal residue (with solids) and more severe residue in the oropharynx (with thin liquids and solids) and hypopharynx (with thin liquids). When airway or pharyngeal residue was present, similar within-subject variability of the amount of residue was appreciated across anatomic landmarks. This is the first study comparing the frequency, severity, and variability of swallowing impairments between PSP and PD populations. Our findings demonstrate more pronounced impairments in swallowing safety and efficiency for PSP compared to PD. These findings provide a clinically relevant characterization of swallowing measures using novel methodological and statistical approaches attempting to resolve some limitations of prior studies.

The Relationship Between Lingual Strength and Functional Swallowing Outcomes in Parkinson's Disease.

The purpose of this retrospective study was to determine whether reduced lingual strength was associated with functional swallowing outcomes in individuals with Parkinson's disease (PD). Participants (N = 42) completed evaluations of maximal lingual isometric pressure (MIP) and mean lingual swallowing pressure (MSP), and flexible endoscopic evaluations of swallowing. Regression models were used to determine the association between lingual strength and functional swallowing outcomes of airway invasion, the presence of post-swallow pharyngeal residue, and the amount of pharyngeal residue (when present). Results revealed that higher MIP (p = 0.002, OR 0.93) and higher MSP (p = 0.001 OR 0.88) were associated with less airway invasion of thin liquids. Both MIP and MSP were able to differentiate between those with and without dysphagia (MIP: AUC 0.7935, p = 0.001; MSP: AUC 0.75, p = 0.026). Neither MIP nor MSP was related to the presence of residue. However, when thin liquid oropharyngeal residue was present, both MIP (p < 0.001, OR 0.99) and MSP (p < 0.001; OR 0.98) were significantly associated with the amount of residue observed. Similarly, when thin liquid hypopharyngeal residue was present, MIP (p < 0.001, OR 0.99) and MSP (p < 0.001, OR 0.98) were associated with the amount of residue observed. These findings suggest a relationship between reduced lingual strength and worse thin liquid swallowing safety and efficiency; however, the magnitude of these effects was small. This indicates that lingual strength is one important contributing factor to functional swallowing impairments in PD and may identify those with unsafe swallowing. These findings have important clinical implications for including lingual strength in the screening, assessment, and management of dysphagia in PD.

Telehealth Management of Dysphagia in Adults: A Survey of Speech Language Pathologists' Experiences and Perceptions.

The goal of this study was to explore telehealth use for dysphagia management in response to COVID-19 to understand variables associated with clinician confidence and perceived effectiveness of this service delivery model and determine clinician-perceived benefits and challenges of managing dysphagia via telehealth. Speech-language pathologists (SLPs, n = 235) completed a web-based survey, providing information on demographics, telehealth use during the pandemic, and perspectives on current and future tele-management of dysphagia. Analyses included descriptive statistics to examine usage patterns; logistic regression to determine which variables were associated with telehealth use, clinician confidence, and perceived-effectiveness; and conventional content analysis to analyze responses to open-ended questions. Results revealed a sharp increase in the tele-management of dysphagia during the pandemic. Years of experience with dysphagia management (p = .031) and pre-pandemic use of telehealth (p < .001) were significantly associated with current use patterns. Working in the outpatient setting was associated with greater clinician confidence (p = .003) and perceived effectiveness (p = .007), and use of guidelines (p = .042) was also associated with greater clinician confidence. Key challenges identified included inadequate technological infrastructure, inadequate patient digital literacy, and reimbursement restrictions. Key benefits were treatment continuity, improving access to care, and time savings. The majority (67%) of respondents reported that they would use telehealth in the future. These findings demonstrate SLPs' abilities and desire to expand their practice patterns to include telehealth for dysphagia management. Therefore, clinician training and more research on best practices for assessment and treatment of dysphagia via telehealth is warranted to refine models of care for dysphagia tele-management.

Attitudes Toward Telehealth Services Among People Living With Parkinson's Disease: A Survey Study.

BACKGROUND: Telehealth has been widely adopted in providing Parkinson's disease care during the coronavirus disease 2019 pandemic. OBJECTIVE: The aim of this study was to survey people living with Parkinson's disease (PwPD) about their attitudes toward and utilization of telehealth services. METHODS: A survey was administered to PwPD via Parkinson's Foundation and Columbia University mailing lists. RESULTS: Of 1,163 responses, 944 complete responses were analyzed. Telehealth awareness was 90.2% (850/942), and utilization was 82.8% (780/942). More than 40% of PwPD were equally or more satisfied with telehealth compared with in-person visits in all types of services used. The highest satisfaction was observed in speech-language pathology appointments (78.8%, 52/66) followed by mental health services (69.2%, 95/137). CONCLUSIONS: In selected circumstances and indications, such as speech-language pathology and mental health services, telehealth may be a useful tool in the care of PwPD beyond the coronavirus disease 2019 pandemic. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson Movement Disorder Society.

Statistical Power and Swallowing Rehabilitation Research: Current Landscape and Next Steps.

Despite rapid growth in the number of treatments to rehabilitate dysphagia, studies often demonstrate mixed results with non-significant changes to functional outcomes. Given that power analyses are infrequently reported in dysphagia research, it remains unclear whether studies are adequately powered to detect a range of treatment effects. Therefore, this review sought to examine the current landscape of statistical power in swallowing rehabilitation research. Databases were searched for swallowing treatments using instrumental evaluations of swallowing and the penetration-aspiration scale as an outcome. Sensitivity power analyses based on each study's statistical test and sample size were performed to determine the minimum effect size detectable with 80% power. Eighty-nine studies with 94 treatment comparisons were included. Sixty-seven percent of treatment comparisons were unable to detect effects smaller than d = 0.80. The smallest detectable effect size was d = 0.29 for electrical stimulation, d = 0.49 for postural maneuvers, d = 0.52 for non-invasive brain stimulation, d = 0.61 for combined treatments, d = 0.63 for respiratory-based interventions, d = 0.70 for lingual strengthening, and d = 0.79 for oral sensory stimulation. Dysphagia treatments examining changes in penetration-aspiration scale scores were generally powered to reliably detect larger effect sizes and not smaller (but potentially clinically meaningful) effects. These findings suggest that non-significant results may be related to low statistical power, highlighting the need for collaborative, well-powered intervention studies that can detect smaller, clinically meaningful changes in swallowing function. To facilitate implementation, a tutorial on simulation-based power analyses for ordinal outcomes is provided ( https://osf.io/e6usd/ ).

Characterizing Quality of Life in Caregivers of People with Parkinson's Disease and Dysphagia.

Caring for a family member with dysphagia can negatively impact caregiver wellbeing, although little is known about how dysphagia severity or specific symptoms influence this. The purpose of this study was to examine how objective measures of dysphagia in people with Parkinson's disease influenced their caregivers' quality of life. Fifty caregivers (mainly spouses) of people with Parkinson's disease completed a caregiver quality of life survey. Results were compared to medical chart reviews, interviews, and instrumental evaluations of swallowing from the care recipients. Outcomes included caregiver quality of life score, ratings of airway invasion and pharyngeal residue, and Parkinson's disease duration. Descriptive and regression analyses were completed. All caregivers reported reduced quality of life, with 28% having severely disturbed adaptation. Every care recipient with Parkinson's disease demonstrated airway invasion and/or pharyngeal residue. Together, the combination of older care recipient age and longer disease duration was associated with poorer caregiver quality of life [adj. R2 = 0.10-0.12, p = 0.03-0.4]. Neither airway invasion nor pharyngeal residue was related to caregiver quality of life (p > 0.05). Findings confirmed that caregivers of people with Parkinson's disease and dysphagia experience reduced quality of life; however, current methods of assessing caregivers' quality of life may not adequately account for dysphagia-specific burden. Results highlight the urgent need for the development of dysphagia-specific assessments of caregivers' quality of life to facilitate identification of high-risk caregivers and aid the development of support systems to improve health outcomes for caregivers and care recipients.

Immediate Effects of Sensorimotor Training in Airway Protection (smTAP) on Cough Outcomes in Progressive Supranuclear Palsy: A Feasibility Study.

Progressive supranuclear palsy (PSP) is a neurodegenerative disease characterized by a high prevalence of dysphagia, cough dysfunction, and resultant aspiration pneumonia. Sensorimotor cough function is important for airway clearance in people with dysphagia. Upregulation of cough has been demonstrated in healthy adults and Parkinson's disease; however, the feasibility of cough rehabilitation in PSP is unknown. We sought to assess feasibility by examining the immediate effects of a novel sensorimotor training in airway protection (smTAP) on upregulation of cough function in PSP. Fifteen individuals with PSP enrolled in this study. Baseline voluntary and reflex cough testing were completed. During smTAP, participants were presented with subthreshold capsaicin and instructed to cough with sufficient intensity to hit a target line (set 25% above baseline reflex peak cough flow) via cough airflow visual biofeedback. Twenty-five repetitions were targeted within a single session. Wilcoxon signed-rank tests compared cough airflow measures between baseline voluntary cough testing, the initial five trials of smTAP, and final five trials. Mean peak expiratory flow rate (PEFR) significantly increased from initial to final smTAP trials (p < 0.001). Fourteen participants increased PEFR, with gains of more than 10% in 11 participants. Variability of PEFR (p = 0.01) and cough expired volume (p = 0.01) significantly decreased across smTAP trials. This study is the first to demonstrate the ability of people with PSP to immediately upregulate cough function, providing preliminary support for the feasibility of cough rehabilitation in this population with this novel treatment approach. Future research examining the effects of multiple sessions of smTAP on cough outcomes is warranted.

Visual Analysis of Swallowing Efficiency and Safety (VASES): A Standardized Approach to Rating Pharyngeal Residue, Penetration, and Aspiration During FEES.

The primary aim of this study was to describe the development of the Visual Analysis of Swallowing Efficiency and Safety (VASES)-a standardized method to rate pharyngeal residue, penetration, and aspiration during FEES. As a secondary aim, we explored the feasibility of training novices to interpret FEES using VASES. Literature review and consensus panel discussions were used to develop standardized rules for VASES. A training protocol was developed and criterion ratings were established. Twenty-five novice raters completed VASES training and pre-/post-training assessments. Statistical analyses were used to examine pre- to post-training differences in the accuracy, reliability, and time to rate each video clip using VASES. Four sets of VASES rules were developed, including 'what', 'where', 'when', and 'how' to rate FEES. Large, significant post-training improvements in rating accuracy were observed across all seven VASES outcome measures (Cohen's d range 0.74-1.59). Additionally, inter-rater reliability increased for four of the seven outcome measures, and the amount of time to rate each video clip decreased from 2.6 min pre-training to 1.5 min post-training. VASES is a standardized FEES rating method used to enhance the subjective analysis of pharyngeal residue, penetration, and aspiration. It can be feasibly taught to novice raters with a high level of success and may be an effective method to analyze swallowing safety and efficiency in clinical and research practices. Future research is needed to test the validity of VASES by examining its relationship with other validated FEES rating scales.

Sensorimotor Cough Dysfunction Is Prevalent and Pervasive in Progressive Supranuclear Palsy.

BACKGROUND: Pneumonia, a leading cause of death in progressive supranuclear palsy (PSP), results from progressive and pervasive deficits of airway protection, including both cough and swallowing dysfunction. Cough protects the airway by expelling aspirate and may be an important therapeutic target to protect against pneumonia in the presence of dysphagia. However, cough has not been objectively characterized in PSP or compared to other common forms of parkinsonism, such as Parkinson's disease (PD). OBJECTIVE: The purpose of this study was to examine voluntary and reflex cough function in PSP, as compared to patients with PD matched for disease duration. METHODS: Twenty-six patients with PSP and 26 with PD completed voluntary and reflex cough testing via spirometry. Linear mixed effects models examined comparisons between groups and within cough types across cough sensory and motor outcomes. RESULTS: Patients with PSP demonstrated significantly reduced cough motor function compared to PD, specifically reduced peak expiratory flow rate (P < 0.001), cough expiratory volume (P < 0.001), and cough inspiratory volume (P = 0.008). Both groups showed similar reflex cough thresholds (P = 0.694), but PSP demonstrated an increased perception of cough stimuli (P = 0.041). CONCLUSIONS: These findings suggest that sensorimotor cough dysfunction is prevalent in PSP, and cough motor deficits, in particular, are worse in PSP than in PD. These deficits likely contribute to the pathogenesis of pneumonia in PSP. Therefore, cough should be integrated into assessments of airway protection and considered as a therapeutic target to potentially reduce adverse health events and improve quality of life in this population. © 2021 International Parkinson and Movement Disorder Society.

Dual Tasking Influences Cough Reflex Outcomes in Adults with Parkinson's Disease: A Controlled Study.

Coughing is an essential airway protective reflex. In healthy young adults, cough somatosensation changes when attention is divided (dual tasking). Whether the same is true in populations at risk of aspiration remains unknown. We present findings from a controlled study testing the effects of divided attention (via a dual-task paradigm) on measures of reflex cough in Parkinson's disease. Volunteers with Parkinson's disease (n = 14, age = 43-79 years) and 14 age-matched controls underwent five blocks of capsaicin-induced cough challenges. Within each block, capsaicin ranging from 0 to 200 µM was presented in a randomized order. Two blocks consisted of cough testing only (single task), and two blocks consisted of cough testing with simultaneous tone counting (dual task). Finally, participants completed a suppressed cough task. Measures of cough motor response, self-reported urge to cough, cough frequency, and cough airflow were collected. Historical data from healthy young adults was included for comparison. Between-group analyses revealed no differences between single- and dual-cough-task responses. However, post hoc analysis revealed a significant relationship between dual-task errors and cough frequency that was strongest in people with Parkinson's disease [p = 0.004, r2 = 0.52]. Specifically, greater errors were associated with fewer reflexive coughs. Unlike healthy participants, participants with Parkinson's disease did not change the number of coughs between the single-, dual-, and suppressed-task conditions [p > 0.05]. When distracted, people with Parkinson's disease may prioritize coughing differently than healthy controls. Abnormal cortical resource allocation may be a mechanism involved in aspiration in this population.

Detection of Aspiration, Penetration, and Pharyngeal Residue During Flexible Endoscopic Evaluation of Swallowing (FEES): Comparing the Effects of Color, Coating, and Opacity.

The aim of this study was to assess the effects of color, coating, and opacity on the detection of aspiration, penetration, and residue during flexible endoscopic evaluations of swallowing (FEES). Thirty dysphagic adults underwent FEES while swallowing five 5 mL thin liquid boluses (1 × each, randomized): white water, blue water, white milk, blue milk, and barium water. To assess the effects of color, blue milk was compared to white milk. To assess the effects of coating, barium, white water, and white milk were compared to each other. To assess the effects of opacity, blue milk was compared to blue water. Videos were blindly analyzed and judged for the presence of pharyngeal residue, penetration, and aspiration. Repeated measures analyses were used to assess differences in the frequency of detection across bolus types. Pharyngeal residue was detected more frequently for liquids that were blue, had a coating effect, or were opaque (p < 0.05) when compared to liquids that were white, did not have a coating effect, or were translucent, respectively. Penetration and aspiration were detected more frequently for liquids that had a coating effect (p < 0.05), but not for liquids that were colored blue or opaque (p > 0.05). Coating appears to be the most important factor detecting thin liquid residue, penetration, and aspiration during FEES. Given these findings, standardized use of boluses that possess a coating effect (e.g., white-dyed water or barium) is highly recommended to enhance the sensitivity of identifying impairments in swallowing safety and efficiency during FEES.

Variability of Voluntary Cough Airflow in Healthy Adults and Parkinson's Disease.

Cough is an important airway protective behavior responsible for ejecting material from the airway to prevent pneumonia, a leading cause of death in older adults and individuals with Parkinson's disease (PD). Variability of motor performance for both spinal and bulbar functions has been documented; however, there are no studies examining variability of cough motor control in PD and healthy controls. The present study examined the effects of age and PD on variability of voluntary cough performance. Twenty-five healthy younger adults (HYA), 26 healthy older adults (HOA), and 16 participants with PD completed three trials of sequential voluntary cough with spirometry. Coefficients of variation were used to examine variability between groups. Increased variability of cough expired volume (p = 0.012) and inspiratory volume (p = 0.006) was appreciated in HOAs compared to HYAs. Participants with PD demonstrated increased variability of cough expired volume (p = 0.029), peak expiratory flow rise time (p = 0.016), and cough volume acceleration (p = 0.034) compared to HOAs. Though participants with PD descriptively demonstrated increased peak expiratory flow rate compared to HOAs, this finding was statistically nonsignificant after adjusting for multiple comparisons (p = 0.072). This study identified that variability in cough airflow increases in healthy aging and Parkinson's disease. These motor control impairments may be attributed to age and disease-related sensorimotor changes in the peripheral and central nervous system. Future research will be necessary to examine the relationship between inconsistent cough motor output, airway invasion, and aspiration pneumonia in PD.

Effects of Verbal Cueing on Respiratory-Swallow Patterning, Lung Volume Initiation, and Swallow Apnea Duration in Parkinson's Disease.

Respiratory-swallow coordination (RSC) is important for swallowing safety. Atypical RSC is common in Parkinson's disease (PD) and is associated with the presence of dysphagia and aspiration. Verbal cueing is known to affect RSC in healthy adults, yet an understanding of its effect on RSC in PD is unknown. Therefore, the aims of this study were to: (1) assess the effects of verbal cueing on respiratory-swallow patterning, lung volume initiation, and swallow apnea duration in PD; and (2) determine when during tidal breathing verbal cues should be given in order to increase the likelihood of eliciting optimal RSC. People with PD were prospectively recruited for respiratory-swallowing assessments during cued and non-cued swallowing conditions. Non-cued trials consisted of swallowing in an unprompted fashion, while cued trials consisted of swallowing only once participants were verbally instructed. Verbal cues were given at four specific points during tidal breathing. Nonparametric tests were used to compare differences in patterning, lung volume, and swallow apnea duration between the cued and non-cued swallows. Twenty-five people with PD were enrolled, yielding an analysis of 375 swallows. Verbal cueing significantly affected respiratory-swallow patterning (p < 0.0005), lung volume initiation (p < 0.0005), and swallow apnea duration (p < 0.0005). The effects of verbal cueing on RSC differed significantly depending on when during tidal breathing verbal cues were given. Cues given at high tidal inhalation were most likely to elicit optimal RSC, while cues given at low tidal exhalation were the least likely to elicit optimal RSC. The results of this study demonstrate that verbal cueing significantly affects RSC in PD. Depending on when verbal cues are given during tidal breathing, RSC can become more safe and coordinated or more atypical and risky. Clinicians should be cognizant of these effects by avoiding verbal cues if attempting to evaluate normal RSC during swallowing evaluations and cueing for swallows at the time of high tidal inhalation when targeting more optimal RSC in PD.

Handheld Cough Testing: A Novel Tool for Cough Assessment and Dysphagia Screening.

Aspiration pneumonia is a leading cause of death in Parkinson's disease (PD), occurring as a result of impaired cough and swallowing function. However, portable diagnostic tools for cough assessment and dysphagia screening are limited. Therefore, the aims of this study were to determine if: (1) 'Handheld Cough Testing' (HCT), a novel tool developed for cough assessments, could detect differences in cough airflow and sensation during reflex and voluntary cough tasks; and (2) HCT could screen for dysphagia in PD with high sensitivity. Twenty-two people with PD underwent HCT and swallowing assessments. Cough airflow ('PEFR') and sensation ('UTC') was recorded during reflex and voluntary cough tasks. Flexible endoscopy was used to identify people with and without dysphagia. Within-subject statistical analyses were used to detect differences in PEFR and UTC across cough tasks and between-subject statistical analyses were used to detect differences in cough function between people with and without dysphagia. Results revealed significant differences in PEFR (p < 0.0005) and UTC (p < 0.0005) across cough tasks using HCT. Additionally, reflex cough PEFR was significantly different between people with and without dysphagia (p < 0.05). A cut-off of 42.5 L/min exhibited an excellent ability to predict dysphagia in people with PD (90.9% sensitivity; 80.0% specificity). This study revealed that HCT was a valid tool for cough assessment and dysphagia screening. It identified differences in cough airflow and sensation during reflex and voluntary cough tasks and screened for people with dysphagia in PD with high sensitivity.

Predictors of Residue and Airway Invasion in Parkinson's Disease.

Dysphagia is a highly prevalent disorder in Parkinson's Disease (PD) characterized by changes in swallowing kinematics, residue, and airway invasion. These changes can lead to serious medical morbidities including malnutrition, aspiration pneumonia, and death. However, little is known about the most predictive causes of residue and airway invasion in this patient population. Therefore, the aims of this study were to (1) assess how disease severity affects residue, airway invasion, and swallowing kinematics in PD; and (2) determine which swallowing kinematic variables were most predictive of residue and airway invasion. A secondary analysis of forty videofluoroscopic swallow studies (VFSS) from individuals with early through mid-stage PD was performed. Airway invasion (Penetration-Aspiration Scale 'PAS'), residue (Bolus Clearance Ratio 'BCR'), and ten spatiotemporal swallowing kinematic variables were analyzed. Statistical analyses were used to determine if disease severity predicted residue, depth of airway invasion, and swallowing kinematics, and to examine which swallowing kinematic variables were most predictive of residue and the presence of airway invasion. Results revealed that residue and the presence of airway invasion were significantly predicted by swallowing kinematics. Specifically, airway invasion was primarily influenced by the extent and timing of airway closure, while residue was primarily influenced by pharyngeal constriction. However, disease severity did not significantly predict changes to swallowing kinematics, extent of residue, or depth of airway invasion during VFSS assessment. This study comprehensively examined the pathophysiology underlying dysphagia in people with early to mid-stage PD. The results of the present study indicate that disease severity alone does not predict swallowing changes in PD, and therefore may not be the best factor to identify risk for dysphagia in PD. However, the swallowing kinematics most predictive of residue and the presence of airway invasion were identified. These findings may help to guide the selection of more effective therapy approaches for improving swallowing safety and efficiency in people with early to mid-stage PD.

Pharyngeal Area Changes in Parkinson's Disease and Its Effect on Swallowing Safety, Efficiency, and Kinematics.

Pharyngeal area can increase as a function of normal healthy aging and muscle atrophy. These increases in pharyngeal area can negatively affect swallowing function in healthy older adults (HOA). However, the presence of pharyngeal area changes and their effects on swallowing function in Parkinson's disease (PD) remain unknown. Therefore, we compared the pharyngeal area of people with PD to HOA to determine if pharyngeal area changes were present in PD above and beyond what is seen in HOA. Within PD, we also evaluated if and how an increase in pharyngeal area affects swallowing kinematics, swallowing safety, and swallowing efficiency. A secondary analysis of videofluoroscopic swallow studies was completed comparing 41 HOA and 40 people with PD. Measures of pharyngeal area, swallowing kinematics, swallowing safety (penetration/aspiration), and swallowing efficiency (residue) were analyzed. An analysis of covariance (ANCOVA) was used to determine if pharyngeal area was significantly different between the HOA and PD groups while controlling for age, sex, and height. Regression analyses were used to examine if and how pharyngeal area influenced swallowing kinematics, swallowing safety, and swallowing efficiency in PD. Pharyngeal areas were significantly larger for people with PD when compared to HOA (p = .008). An increase in pharyngeal area was associated with less pharyngeal constriction (p = .022), shorter duration of airway closure (p = .017), worse swallowing safety (p < .0005), and worse swallowing efficiency (p = .037). This study revealed that pharyngeal areas are larger in people with PD when compared to HOA, and that this increase in pharyngeal area is associated with maladaptive changes to swallowing kinematics, residue, and penetration/aspiration. These findings support the notion that pharyngeal muscle atrophy may be exacerbated in PD above and beyond what is seen in normal, healthy aging group. Results from this study highlight the need to consider pharyngeal muscle atrophy as a source for swallowing dysfunction in PD, and as a potential treatment target for swallowing rehabilitation.